Odd and Even Product

<?php

$numbersString = "2 1 1 6 3";
$numbers = explode(" ", $numbersString);

//print_r($numbers);
$oddProduct = 1;
$evenProduct = 1;

for ($i = 0; $i < count($numbers); $i++) {
    if ($i % 2 == 0) {
        $oddProduct *= $numbers[$i];
    } else {
        $evenProduct *= $numbers[$i];
    }
}

if ($evenProduct == $oddProduct) {
    echo "yes <br />";
    echo "product = $oddProduct";
} else {
    echo "No <br />";
    echo "odd_product = $oddProduct  <br />";
    echo "even_product = $evenProduct";
}